1. Field of the Invention
The present invention relates to an organic light emitting device which has an organic light emitting element, and an emissive display device using a plurality of organic light emitting elements. Particularly, the present invention relates to an organic light emitting device and display device which have enhanced light extraction efficiency from light emitting pixels.
2. Description of the Related Art
In emissive elements such as an organic EL element, a part of light emitted from the light emitting element, for example, incident light at an angle larger than the critical angle on an interface between an element substrate and air is totally reflected. Therefore, there has been a problem that only about 20% of the total emitted light could be actually extracted to the outside. Then, a technique for by forming irregularities on the light extraction surface of the light emitting element to enhance light extraction efficiency has been proposed.
As such a technique, a technique in which a circularly polarizing plate and a micro lens are stacked in this order on the surface of an organic EL display having a emissive light source has been disclosed (see Japanese Patent Application Laid-Open No. 2002-216947).
A technique in which a dual brightness enhancement film and a circularly polarizing plate are stacked in this order on the surface of an organic EL element having a emissive light source has been disclosed (see Japanese Patent Application Laid-Open No. 2004-070094).
However, since the organic EL display disclosed in Japanese Patent Application Laid-Open No. 2002-216947 cannot prevent external light from reflecting on the surface of the micro lens, an effect of preventing the external light from reflecting cannot be sufficiently obtained.
The organic EL element disclosed in Japanese Patent Application Laid-Open No. 2004-070094 cannot sufficiently prevent the reflection of external light incident from an oblique direction.